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प्रश्न
What is PCR? Explain different steps involved in it.
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उत्तर
Definition: Polymerase Chain Reaction (PCR) is the process of in vitro amplification of gene of interest using a PCR machine.
Mechanism of PCR: At the start of PCR, all the requirements are mixed together in ‘eppendorf tube’ and the following operations are performed sequentially:
Step i: Denaturation
The reaction mixture is heated to a temperature (90–98o C) to separate two strands of desired DNA. This is called denaturation.
Step ii: Annealing
The mixture is allowed to cool (40–60o C) that permits pairing of the primer to the complementary sequences in DNA. This step is called annealing.
Step iii: Primer extension / Polymerization
The temperature (70–75o C) allows thermostable Taq DNA polymerase to use single-stranded DNA as template and adds nucleotides. This is called primer extension. It takes around two minutes duration.
संबंधित प्रश्न
Bt-cotton shows adverse effect on the population of which butterfly?
The gene transfer between unrelated plants is brought about by ____________.
A technique used to make numerous copies of a specific DNA segment quickly and accurately is called ______
Which vector is mostly used in rDNA technology in plants?
The given figure is the diagrammatic representation of the E. coli vector pBR322. Which one of the given options correctly indentites its certain component(s)?
Which of the following statements are true about cloning vectors?
- Vectors are DNA molecules that carry a foreign DNA segment.
- The replicated DNA is introduced into the host cell.
- It possesses the origin of replication (Ori).
- Vectors may be plasmid, bacteriophage, Yeast artificial chromosomes (YACs), etc.
- Vectors do not require a selectable marker to identify and eliminate non-transformants.
Choose the correct answer from the options given below.
Name the source of thermostable DNA polymerase.
Assertion: In a bioreactor, it is not necessary to maintain sterile ambience.
Reason: Sterile conditions promote the growth of unwanted microbes in the culture medium.
Suneeta is planning an experiment to clone a gene in a vector. So, she has to choose a good cloning vector.
Which one of the vectors shown below should she choose? Justify your answer by giving two reasons.
 |
 |
 |
| Vector A | Vector B | Vector C |
Give a reason for the following:
The diagram given below represents vector pBr322 which was modified by a research scholar Dr. Rayon, but the vector was rejected by his guide.
